turtle

Feeding the Green Turtles

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Phoenix, the Green Turtle, moves in to eat some lettuce.

Of all the animals I fed on my Marine Biologist Day at the London Aquarium, the most majestic and magnificent animals of all were the two Green Turtles, Boris and Phoenix. In the large tank of the London Aquarium, you can find sharks, rays and other interesting marine life, but most beautiful of all are these giants of the ocean. Chomping on lettuce, Monica and I fed these behemoths towards the end of the day from the open top of the tank. Green Turtles like Boris and Phoenix become vegetarian as they grow up, and so adult like them are fed lettuce, although they still try to steal food, like squids, from the others animals. In order to remain true to their natural diet, which would consist of seaweeds and kelp, the aquarium makes sure to avoid giving them any kind of meat.

Green Turtles, also known as Chelonia Mydas, are found across the globe, as far north as Britain and south Alaska, and as far down as The Cape of Good Hope. They have particularly large nesting grounds in areas of the Caribbean and Indo-Australia, where they will climb onto land to lay their eggs. Rain Island in the Great Barrier Reef is a huge hotspot for these amazing animals, with many thousands of them dragging themselves up the small strip of land in order to find the best spot to conceal their eggs. Going onto land can be vary dangerous for them, so they will make the journeys from dusk until dawn, to avoid being caught out in the baking sun. Unfortunately as the tide moves out, many turtles cannot make it back to land and are caught left as food for birds and scavengers.Boris takes food from the end of my stick.

Boris and Phoenix surface to take some food I've left in the water.

Adult Green Turtles are about one and a half metres in length and can weigh up to 200kg, although certain exceptional specimens have been up to just under 400kg. Their bodies are a brownish colour, although some individuals have a more mottled pattern. Hatchling start off jet black, with a yellow or white underbelly, and as they grow, begin to develop their unique colour and pattern on the shell, that allows humans to identify individual members of the species. The tails of males are far larger and longer than those of females, which makes it easy to sex the turtles. They are rather unremarkable when compared to their close relatives, with most differences occurring around the mouth and head area, although they are the only turtle that become a herbivore when it matures. Peculiarly, the ‘green’ in the name does not feature visibly on the turtle, instead being attributed to the greenish fat layer beneath the skin. They were named by sailors who hunted and ate them on their long voyages.

The heavy shell of all larger turtles makes for a safe life of eating jellyfish and nibbling on sea kelp, but tiger sharks are still a valid threat to an adult sea turtle. The Tiger Shark has a massively powerful bite, beaten only by the Bull Shark (as well as the Nile and Saltwater Crocodile), and it more than capable or crushing through the shell of a Green Turtle in a couple of bites. As such the adult turtle will turn its body on its side in order to present as larger surface to the shark, which it cannot get its mouth around. Tiger Sharks will often wait for dead turtle bodies to be washed into the ocean of laying season, since they provide easy sources of protein. In this way, turtles are still relatively safe from these sharks, who would rather find an easier target. Juvenile turtles, however, are in much greater danger of being eaten. Eggs are dug up my land mammals as nutritious snacks, birds snatch newly hatched turtles from the sand as they run for the sea, and crabs will easily tear a baby turtle limb from limb. Luckily, with such a large number being born every year, turtles are fairly safe from their natural predator. Unfortunately, turtles are hunted for their flippers to be used as food and ‘traditional medicine’. It is a horrible waste of life, and needs to be stopped if we are to conserve these gentle giants for the future.

I had a brilliant time with Boris and Phoenix, and I must confess that I really love turtles, be they green or loggerhead. Here’s hoping that I have many more opportunities to see them in the future.

Chinese Soft-Shelled Turtle

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I feed Rufus the Chinese Softshelled Turtle.

In the back rooms of the London Aquarium, many animals deemed to aggressive to go into the display tanks live in their on private biomes. One such animal is Rufus, the Chinese Soft-Shelled Turtle. As a rule, these strange turtles are angry and short-sighted, which makes them likely candidates for biting the fingers of children who leave them trailing in the open pools around the aquarium, so as you might imagine he is kept safely away. Rufus was donated to the aquarium by a pet owner who no longer had the resources to feed him, or simply got bored of him. While is was better to donate Rufus than to abandon him in a local pond, far too many people donate their pets each year, and this can cause problems for the aquarium, who can only house so many. It’s far better to keep your turtle, or sell them to a local pet shop where they can have a new owner.

The Soft-Shelled Turtle, or Pelodiscus Sinensis, despite its name has a shell no softer than that of any other turtle, instead owing its name to the lack of sharp ridges that cover the shells of most turtles and the flexible edges that their shells have. The centre of the shell (or carapace) is made of bone and as hard as any other species. In general, Chinese Soft-Shelled Turtles are a dark khaki colour across their shell and on their limbs, like Rufus, but some have a more mottled, blotchy colouration. Several darker lines can often be seen around the head area, but they are difficult to spot on Rufus, since he seldom stops moving when people are near. The strange shape of the nostrils, that resemble long tubes, are used as snorkels to breath below the water. They are also useful as they are able to release waste products from that area, which means they don’t lose much water from urinating. This is useful because these turtles live in areas where salt water and freshwater mix, meaning the slightly salty water is often bad to drink.

Chinese Soft-Shelled Turtles eat mainly invertebrates, crustaceans like shrimp and small fish in the wild, which are plentiful in their habitats. However, these turtles are rather opportunistic and have been known to eat plant life, and in captivity, pet food and small vertebrates like mice and young frogs. Be warned though, they don’t make for good ratters. I fed Rufus with a few frozen prawns, which he swam up to the surface to receive. Keeping my fingers out of the way, I waved the food in the water until he smelt it and came to me, and then I released it in front of him so that he could take it away. Unfortunately, Rufus has fairly poor eyesight, and at one point did not see me release the food, where upon it sank to the bottom, with Rufus looking at me angrily and expectantly. He found it eventually, but not after a few malicious looks at my fingers.

In China, people eat soft shelled turtles fairly regularly, even to the point where they are farmed, with many millions being eaten nationally. They are often made into a sort of turtle soup, or stewed with vegetables, and are fairly nutritious. In Japan these turtles are considered a delicacy, and can be eaten in a variety of ways. In the West, they are mainly kept as pets, like Rufus before he came to the aquarium, and you can find them in larger pet shops across the country. Luckily, these turtles are in plentiful supply, and are unlikely to ever be in danger of extinction.

After feeding Rufus his fill of frozen prawns, I waved goodbye to him and went on to feed some of the larger, flatter denizens of the aquarium.